Availability
COMTEK Baluns, UNUNs and Chokes
COMTEK CFC-50X Common Mode Feedline Chokes
COMTEK CFC-50X Common Mode Feedline Chokes are designed to suppress unwanted RF currents on the outside of the shield on coaxial feedlines. These 1:1 inline coaxial feedline chokes are built with fifteen Mix-31 ferrite beads on premium DX Engineering RG-8X coaxial cable, offering improved performance for a wide variety of antenna systems. COM-CFC-50X Key Benefits: • Provides Effective Shield RF Current Suppression from 1.8 to 54 MHz, helping eliminate common mode currents that cause RF feedback and noise inside the feedline. • Consistent and balanced pattern across frequency range: Excellent RF choking isolating the feedpoint prevents current imbalance, which preserves radiation pattern and antenna performance.
( 3 )
$59.99
COMTEK Current Feedline Chokes
The updated COMTEK CFC-50A 50 ohm Feedline Chokes consist of 75 heavy-duty mix-31 RF choke beads on a length of RG400 PTFE coax terminated at both ends with silver-plated PTFE PL-259/UHF male connectors and the correct length of heat-shrink tubing. COMTEK Current Feedline Chokes ensure that stray RF does not flow on the outside shield of your feedlines. They are typically installed at the antenna feedpoint connection. They may also be used where a long run of feedline leaves a remote antenna switch or a tower. They are also very effective at the shack end of a long run of on-the-ground or above-ground coaxial feedline, to block unwanted RF signals and noise picked up on the shield. These chokes provide excellent common mode impedance and handle up to 5 kW from 1.8 to 54 MHz. These chokes are assembled except for the tubing needs to be installed and heat-shrinked after the choke is positioned as it will be installed.
( 14 )
$131.49
Clearance
COMTEK Jerry Sevick W2FMI Series Current Baluns
COMTEK Jerry Sevick W2FMI Series Current Baluns were inspired by the writing of Jerry Sevick, as published in his book "Understanding, Building, and Using Baluns and Ununs" also available from DX Engineering. COMTEK baluns are value-engineered for maximum performance at a reasonable cost. They provide a superb, efficient transition between unbalanced coax and balanced antennas. COMTEK Baluns feature: * Jerry Sevick design with modern improvements from DX Engineering's in-depth balun research and development * Unique high-voltage compensating capacitors for unequaled SWR bandwidth * Outstanding ferrite-mix coated toroid core with special design to accommodate close coupling without excessive stress * Exceptionally high and consistent common mode impedance across the specified bandwidth, which provides isolation where it is needed most * Special wire size selection and Teflon-insulated wire sleeves provide exact impedance matching and superb insulation, unlike common Thermaleze wire * Typical insertion loss is less than 0.2 dB * Power handling on HF is 3 kW CW and 5 kW SSB on single core models, 5 kW CW and 7 kW SSB on dual core models * May be used to 54 MHz with reduced ratings * Gasketed SO-239 connectors are silver plated and have Teflon insulation * Sealed in a weatherproof 4 in. x 4 in. x 2 in. NEMA box * Stainless steel hardware Note: Polarity markings on baluns are used for matching phase on balanced antennas when stacking beams for a phased array. Also, the positive terminal should be connected to a vertical element or Inverted-L and the negative terminal goes to the radials. For most regular applications on one antenna, including beams, dipoles and most wire antennas, balun polarity doesn't matter. The best Amateur Radio baluns in the world are from DX Engineering. That includes COMTEK Jerry Sevick W2FMI Series Current Baluns!
( 10 )
$104.99
$68.24